As a technique of improving the reliability of the recording and reading of the record data on a high-density recording medium, such as an optical disc, a magnetic disc, and a magneto optical disc, there is defect management. Namely, when there are scratches or dusts, or deterioration (which are collectively referred to as a “defect”) on the recording medium, the data to be recorded or already recorded at the position of the defect is recorded into another area on the recording medium (which is referred to as a “spare area”). In this manner, by evacuating the record data, which is possibly imperfectly or incompletely recorded or read because of the defect, to the spare area, it is possible to improve the reliability of the recording and reading of the record data (refer to Japanese Patent Application Laying Open NO. Hei 11-185390).
In general, a defect list is made to perform the defect management. On the defect list, there are recorded address information for indicating the position of a defect on the recording medium, and address information for indicating the position of the spare area (e.g. a recording position in the spare area) to which the data to be recorded or already recorded at the position of the defect is evacuated.
In general, the defect list is made when an initial logical format for initializing the recording medium or recording file-system data or the like is performed. The defect list is also made when the record data is recorded onto the recording medium. When the record data is recorded and rewritten several times, the defect list is made or updated whenever the record data is recorded and rewritten and a defect area is detected, or whenever the record data is evacuated to the spare area. Moreover, the defect list may be made when the record data is reproduced from the recording medium. For example, if a predetermined number or more of data is error-corrected with respect to a predetermined unit (e.g. a sector unit or and a cluster unit) of the record data when the record data is reproduced, the predetermined unit of the record data is judged or determined to be a defect which cannot be error-corrected in the future and will be an object of the evacuation. As described above, the defect list is made or updated whenever the record data is evacuated to the spare area.
When the record data is recorded onto the recording medium, the defect list is referred to. This allows the recording of the record data onto the recording medium away from the position of a defect. On the other hand, the defect list is also referred to when the record data recorded on the recording medium is reproduced or read. This makes it possible to surely read both the record data recorded in a normal recording area and the record data recorded in the spare area because of the presence of a defect, on the basis of the defect list.
If the defect list is managed by a recording apparatus itself for recording the data, the defect list is generally recorded into a specific area on the recording medium, which is the object of the making or updating of the defect list. The defect list is read from the recording medium when the record data recorded on the recording medium is reproduced or when other record data is rewritten or additionally recorded (i.e. written once). Then the defect list is referred to in a reading operation by a reading apparatus or in a reproduction operation by a reproducing apparatus.